The present invention is directed generally to an apparatus for repairing and straightening vehicles and more particularly to a passenger vehicle straightening apparatus adapted to provide for the facilitated entry of a car or truck therein and the application of forces from various directions to straighten the body thereof.
Several automobile body straightening apparatus are commercially available but these have several problems. Chisum U.S. Pat. No. 3,888,100 is an example of such an existing apparatus. The Chisum apparatus generally includes a plurality of towers movably positioned about a vehicle with each tower having a chain connected to the vehicle for exerting a pulling force toward the tower. The towers have been supported for revolution about a center pivot point, however, this arrangement does not accommodate proper positioning of the towers relative to an elongated vehicle body. FIG. 4 of Chisum shows a push rod 105 mounted on a cylinder 57 with a pull chain 102 anchored to a push rod cap means 103. The push rod turns a full 360.degree. such that a pull can be exerted on the vehicle frame from any point around the tower. A ring means 123 may be rotated around the tower to position the chain at the desired location. The cylinder cannot be connected directly to the cap 103 since the lateral pull by the chain would damage the piston rod. Furthermore, the chain cannot be attached to the cylindrical means 113 since it needs to be movable around the tower. Approximately 20% of the power of the hydraulic cylinder is lost due to the friction between the push rod and the inside of the cylindrical means resulting from the lateral pressure created by the pull of the chain. Also, the length of the chain cannot be easily adjusted since the anchoring point at the cap 103 is too high to reach without a ladder. The ring means is a friction lock arrangement which is not positive and can walk up the tower. Likewise, the towers generally do not provide for the application of forces from sufficient heights to straighten certain body parts.
In straightening vehicles, it is often desirable to have access to the vehicle from below. Conventional straightening apparatus are therefore often placed over a pit which permits a person to get beneath the vehicle. Alternatively, apparatus installed on a flat floor often have a vertically adjustable ramp or the like that the vehicle is driven or winched up upon. Construction of pits in floors is costly as is the need for a winch to pull disabled vehicles upward on a ramp. Both the ramp and the pit arrangements limit practicality of the apparatus.
Newer unibody vehicles all present an additional problem in that there is no frame over which a chain can be strapped to tie the vehicle down to the apparatus.
These and other problems associated with the prior art are believed to be solved by the vehicle repairing and straightening apparatus of the present invention.
Accordingly, it is a primary objective of the present invention to provide an improved apparatus for repairing and straightening vehicles.
Another objective of the present invention is the provision of a vehicle straightening apparatus which can be installed on a flat floor and be uniformly raised and lowered.
A further objective is the provision of an apparatus for repairing and straightening vehicles having a tower assembly with a vertically oriented hydraulic cylinder mounted thereon which is extensible in a downward direction.
A further objective is to provide a vehicle straightening apparatus for use on passenger vehicles.
A further objective of the present invention is the provision of a portable vehicle straightening apparatus.
A still further objective of the present invention is the provision of a vehicle straightening apparatus including means for efficiently exerting pulling forces therefrom with a minimum loss of power.
Yet another objective of the present invention is the provision of a vehicle straightening apparatus which vehicles can easily enter and exit from.
A more specific objective is to provide a vehicle straightening apparatus including a two-tiered U-shaped track arrangement open at one end for the entry and exit of vehicles therethrough.
A further objective of the present invention is the provision of a vehicle straightening apparatus adapted for easy operation by one person.
A further objective of the present invention is the provision of a vehicle straightening apparatus for use on unibody vehicles.
A further objective of the present invention is the provision of a vehicle straightening apparatus with an overhead hoist movable along the length of the apparatus and from side to side thereon.
A further objective of the present invention is the provision of a vehicle straightening apparatus wherein pulling force is applied to the vehicle from the adjacent tower assemblies in a direction perpendicular to such tower assemblies.
A further objective of the present invention is the provision of a vehicle straightening apparatus wherein upward or downward pulling forces can be applied anywhere upon the vehicle.
Yet another objective of the present invention is the provision of a vehicle straightening apparatus wherein the pulling force applied to the vehicle equals the force developed in the hydraulic power cylinder.
Still another objective of the present invention is the provision of a vehicle straightening apparatus in which the displacement of the hydraulic power cylinder is equal to the displacement of the tension member, which is connected to the vehicle, to which the pulling force is applied.
These and other objectives of the present invention will be apparent to those skilled in the art from the following description of the invention.